Opto-refractor meter.



P. B. HUGHES.

OPTO-REFBAGTOR METER.

APPLICATION FILED JULY 27, 1908.

929, 1 3.4. Patented Jul 27, 1909., s-jg Em 1.

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OPTO-REFRAGTOB METER.

APPLICATION nun JULY 27, 190B.

Patented July 27, 1909.

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'F.B.HUGHES. OPTO-REFRAGTOR METER.

APPLICATION FILED JULY 27f1908i.

929, 34. Patented July 27, 1909.

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F. B. HUGHES.

OPTO-REPRAGTOR METER. 'APPLIOATION FILED JUIY27, 1908.

Patented July 27. 1909.

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FRANK B. HUGHES, OF INDIANAPOLIS, INDIANA.

OPTO-BEFRACTOR METER.

Specification of Letters Patent.

Application filed July 27, 1908.

Patented July 27, 1909.

Serial No. 445,468.

To all whom it may concern:

Be it known that I, FRANK B. HUG-HES, a citizen of the United States,residing at in dianapolis, in the county of Marion and State of Indiana,have invented certain new and useful Improvements in Opto-EefractorMeters; and I do declare the following to be a full, clear, and exactdescription of the invention, reference being had to the accompany ingdrawings, and to the letters and figures of reference marked thereon,which form a part of this specification.

This invention relates to eye-testing and measuring instruments that aredesigned to be used by Opticians and oculists, the invention havingreference particularly to apparatus whereby the practitioner may readilyexamine and ascertain the nature or character of all ocular errors ofrefraction and defects of the human eye, and be enabled to determine theproper remedy therefor.

Objects of the invention are to provide improved eye-testing andmeasuring appara tus or a machine by which to eliminate uncertaintiesand inaccuracies common to methods of examination by trial frames andlenses, also to facilitate examinations by both the subjective andobjective tests forall ocular errors of refraction Without unduly tiringthe patient; a further object being to provide means for prom tlyindicating to the optician by monocu ar tests the character and strengthof eye-glasses that may be required by a patient under examination tocorrect defects of vision.

The invention consists in an opto-refractormeter comprising broadly ahousing to afford a dark-room for objective tests and to exclude laterallight rays from the lenses of the apparatus when making subjectivetests, a stationary or relatively-fixed lens and a movable or adjustablelens and a target and also a lamp mounted in the housing, the movablelens being movable along a perfect optical axis and mounted on a carrierthat is provided with a pointer which is visible above the housing, alensholder mounted on the front of the housing and holding a lensremovably, and a scale on the top of the housing to be read as indicatedby the pointer for ascertaining lens numbers required; all necessarylenses of the apparatus bein alined; the distance of one lens fromanother at a given point producing a lens whose focal length equals instrength the lens designated by the pointer by number on the scale onthe housing. And, the invention consists specifically in the novelfeatures of construction of the apparatus, and in the parts andcombinations and arrangements of parts, as hereinafter particularlydescribed and defined in the appended claims.

Referring to the drawings Figure 1 is a side elevation of the apparatus,a portion of the housing thereof being broken away; Fig. 2, an endelevation; Fig. 3, a top plan with a portion of the housing broken away;Fig. 4, a transverse sectional view on the line AA in Fig. 3 Fig. 5, aside elevation of the apparatus without the housing; Fig. 6, an endelevation without the housing; Fig. 7, a top lan without the housin Fi 8a fragmenr i 7 t.

tary end elevation of the housing; Fig. 9, a longitudinal verticalcentral sectional view of the apparatus in which a portion of the eyeshield is broken away; Fig. 10, a transverse sectional view on the lineC-C in Fig. 5; Fig. 11, a transverse sectional view on the line DD inFig. 5; Fig. 12, a fragmentary sectional view approximately on the lineCC in Fig. 5 on an enlarged scale; Fig. 13, a plan view of the scalecard and scales or tables thereon that is used on the top of thehousing; Fig. 14, a transverse sectional view on the line EE in Fig. 7;Fig. 15, a fragmentary vertical sectional view on the line F in Fig. 3Fi 16, a transverse sectional view on the line G in Fig. Fig. 17, afragmentary elevation of the movable lens carrier and pointer thereon;Fig. 1.8, a fragmentary top plan of the carrier and pointer; Fig. 19, afront elevation of the target holder and targets thereon; Fig. 20, afront elevation of the chart; and Fig. 21, a front elevation of thecircular plate having degrees of the circle thereon which forms a partof the lens sup porter on an end of the housing.

Similar reference characters throughout the drawings indicatecorresponding ele ments or features of construction referred to herein.

The specific apparatus shown herein as illustrating the preferredconstruction of the invention comprises a base 1 preferably havingrubber feet 2 and a main frame mounted on the base, a part of the frameconstituting a housing covering some of the operative parts as willfurther become apparent. vVhile the apparatus may be constructed invarious sizes it is preferable that it be of convenient dimensions so asto be portable and not oocupy unnecessary space and also so as to beconvenient in use, a suitable length being about twenty inches, more orless. The frame comprises preferably a pair of side sills 3 and 3 andend sills 4 and 5, all secured sui ably to the base 1 and preferablyconnected together. The housing has two sides 6 and 7 and two ends 8 and9 connected together, and a partition connected to the sides and havinga" circular aperture 10 therein, the partition being arranged somewhatnear to the end 9, a top 11 being connected to the sides and ends and.also to the partition, the housing being mounted removably on the base 1and extending about the frame members that are secured. to the base. Thehousing preferably is formed of sheet metal and covered with blackenamel or paint on the interior thereof. The top 11 has a longitudinalslot 11 therein and has also an aperture 11" therein near the end 9 forthe escape of heat from a lamp which may he used in the housing. The end9 has an aperture or doorway 9 therein that is normally covered by adoor 12 that is connected by a hinge '12 to the end. The side 7 of thehousing has a recess 7 in the lower portion thereof, and the sill 3 hasa filling piece 7 thereon that is of the same length but slightly lessheight than the recess, leaving a clearance space between the top of thefilling piece and the lower edge of the side 7 in the recess 7 said side7 having also two slots 13 and 13 in the lower part thereof. The end 8has an aperture 8 therein that is circular and arranged opposite to theaperture 10 in the partition 10, the door-way 9 being opposite to theaperture 10 so that either a patient or a practitioner may look throughthe housing.

It is designed that the housing shall support one or more lensesremovably and also an eye shield and head rest for the patient, and forthis purpose two guide members 14 and 14 are secured to the end 8 of thehousing and have a stop plate 15 connected thereto, there being twoguide rods 16 and 16 arranged vertically and attached to flanges 17 and17 of the guide members, a lens supporter 18 being guided by the flangesand having also a pair of guide blocks 19 and 19 attached thereto andengaging the rods 16 and 16, the supporter normally resting on the plate15 and movable vertically; The supporter 18 has an aperture 8 thereinopposite to the aperture 8, and an annular plate 20 is attached to theouter side or front of the supporter so as to extend about the aperture,the front of the plate having graduations 21 thereon and numerals 22indicating degrees of the circle. An annular lens holder 23 is suitablyguided rotatively between the supporter 18 and the plate 20 and has gearteeth 24 arranged in a circle thereon. A spindle 25 is rotativelymounted on the supporter 18 and has a hand-wheel 25 attached thereto andalso a pinion 26 secured to the spindle and engaging the gear teeth 24whereby the holder may be rotated, the holder having a lens receptacle27 mounted thereon so that a lens when inserted in a receptacle may beturned rotatively by means of the wheel 25. A lens receptacle 28 ismounted on the supporter 18 and will hold the lens in stationaryposition opposite the aperture 8 and between the aperture and the lensthat may be placed in the receptacle 27. A plate 29 is mounted in guides30 and 30 with which the members 14 and 14 are provided and has twocircular apertures 31 and 31 therein and is also provided with a shield32 on the outer side thereof against which the patient may steady hishead while looking into the housing, the plate 29 being movable so thateither aperture therein may the eye of the patient and at one side ofthe slot 34 is a scale 36 showing numbers indicating the character oflenses for eye the scale having a heading 3? designating that thenumbers of lens are for myopes. At the opposite side of the slot is ascale 38 having numbers of lenses arranged in reverse order to that ofthe scale 36 and having a heading 39 at one end thereof. Also a tableheading 41 denoting age of eye, and adjacent to this table is a table 42having a heading 43 denoting amplitude of accommodation. Adjacent to thescale 38 is a heading 44 th for denoting scale hyperoietro iiia and prbyopia. Two glass plates 45 and 40 are arranged on the top of the scalecard and are suitably secured to the top of the housing.

A lens frame 46 has a hinge member 47 48 to a rotative shaft 49 providedwith a handle 50, the shaft being mounted inbearings 51 with which theend sill is provided, the shaft extending through a suitable slot (notshown) in the side 6 of the housing. A con vex lens 53 is suitablymounted on the frame 5 46 so as to be normally stationary, but as willbe seen the frame 46 may be moved on its hinge so as to lieapproximately horizontal, thus causing the -ens to disappear from view,the lens when in use being constantly opposite to the opening 8 and at asuitable v predetermined distance from the end 8, the 1 frame 46normally standing against a stop l 54 that is mounted on the end sill 4so that be brought opposite to the lens 33 in the rescale card is ascale 35 denoting inches from I 3 40 is arranged on the scale card andhas a formed thereon that is secured by a set screw .1

the frame will be practically stationary when in operative position andbe vertical. A pair of guide bars and 55 are mounted on the end sills 4and 5 so as to be horizontal, and a cross head 56 is mounted slidinglyon the guide bars and provided with a stop 56 on the top thereof, thecross head forming a part of a carrier for the movable or adjustablelens, the carrier comprising also a frame 57 that has a hinge member 58formed thereon which is secured by a set screw 59 to a hollow shaft 60provided with a handle 61 and mounted rotatively on the cross head 56 insuitable bearings, a concave lens 62 being suitably mounted on the frame57 so as to be movable between the lens 53 and the aperture 10 that isin the partition if). The shaft 60 extends out in the space above thefilling piece 7 and may be used for moving the carrier toward or fromthe lens 53, and by turning the handle 61 the lens 62 may be caused todisappear out of range by moving the frame 57 down to an approximatehorizontal position as indicated by dotted lines in Fig. 9. A hingemember 63 is attached to the frame 57 and has a frame 64.- hingedthereto, and a transparent chart 65 is mounted on the frame and hassuitable words 65 thereon of suitable size for the purpose, the chartbeing normally supported by the frame opposite to the lens 62, or theframe may swing away so as to cause the chart to disappear from view.For operating the frame a shaft 66 is used as a hinge-pin for connectingthe 5 frame ti l to the hinge member and is suitably secured to theframe, being rotative in the hinge member and has a pinion. securedthereto, the shaft being journaled in a bearing 68 that is attached tothe frame 57. A shaft 69 is rotatively mounted in the hollow shaft 60and is provided with a handle 70 on the outer end thereof, and on itsinner end has a gear segment 71 secured thereto which is in engagementwith the pinion 67, so that the frame may be moved by turning the handle70.

A. shaft 72 is mounted rotatively in suitable hearings on the end sill land has a sprocket wheel 73 secured thereto, the shaft extending outthrough the slot 13 and having a hand-wheel 74 secured to the outer endthereof for turning the shaft. A sprocket wheel 75 is suitably mountedrotatively on the sill 5, and a sprocket chain 7 6 is connected with thetwo sprocket Wheels 73 and 75 and also attached to a lug 77 with whichthe cross head 56 is provided in order to adjust the position of thelens 62 with accuracy or to move it as it may be desired. in some cases,however, this gearing may be omitted and the cross head may be moved andadjusted solely by means of the handle 61.

A stem 78 is mounted in a bearing 57 with which the upper end of theframe 57 is provided and is adjustable rotatively, the top of the stemhaving two pointers 79 and 79 thereon, and when the pointers areproperly adjusted the stem may be moved through the slot 11 in the coverof the housing, the stem normally standing upright with the pointerextending transversely of the slot so as to point to the scales at theside of the slot. he bearing 5 has notch 80 in the top thereof, and thestem 7 9 has a collar 81 thereon provided with a projection 81 thatnormally extends into the notch for holding the pointers in normalpositions, a spring 82 being arranged on the lower end of the stem andseated against an arm 83 that is attached to the stem for limiting therotative movement of the stem when turned so as to ermit the housing toberemoved, the spring )eing seated also against the bearing 57.

A target frame 84 is suitably supported on the frame sill 5 and has apivot 85 on which a target holder 86 is rotatively mounted, the holderhaving a circular aperture 87 therein and other suitable apertures atone of which a target 88 is mounted and having letters 88" thereon ofsuitable sizeproportionate to the dimensions of the apparatus, anothertarget 89 having suitable characters 89 thereon and still another target90 having suitable characters 90 thereon, the target 90 being preferablyblack along its marginal portion, and the front surface ofthe holder 86is preferably black, the targets being transparent. The back of thewheel 86 is provided with four projections 91, 92, 93, for itsoperation. A horizontal guide is mounted on the frame sills and has apull-rod 96 mounted slidingly therein and so to move rotatively also,the pull-rod extending through the slot 13 in the housing side 7 andhavof the pull-rod having an arm 98 thereon adapted to he moved intoenga ement with the projections on hack of the target holr er to movethe holder rotatively, for the purpose of changing the targets, the armbe ing designed to engage a stop 95 after having changed the positionsof the targets. When retracting the pull-rod it is rotated slightly soas to permit the arm 98 to pass by the end of the projection that to benext engaged by the arm, and then the pull-rod should be movedrotatively to cause the arm to engage the projection.

An incandescent electric lamp 99 is mount ed in a socket 100 which ismounted on the base 1 between the end 9 and the partition 10, the framehaving a coupler 101 mounted thereon which is connected by a circuitwire 102 with the lamp, the coupler adapted to have a feed-Wire 103connected thereto or disconnected therefrom for conducting a currentfrom any suitable source of electricity. The lamp bulb or glohe ispreferably frosted or ground to soften the light therefrom. A

reflector 104 is mounted rotatively on the mg a handle 97 on its outerend, the inner end I. TO

socket 100 so as to be adjustable to reflect the light either toward theaperture 10, or in the opposite direction toward the aperture 9, orthrough the latter aperture when the door 12 is open when thepractitioner examines the eyes of the patient.

It should be understood that many and various modifications may be madein the details of construction of the apparatus within the scope of theinvention, and it will be understood that various kinds of lenses may beused in the receptacles 27 and 28 and that two lenses may be usedtherein for mixed astigmatism. In the receptacle 27 a cylindrical lensor sphere will be suitable in some cases and in some cases a concavelens will be suitable in the receptacle 28. The lens supporter 18 is tobe elevated to receive the lenses conveniently when changes of lensesare required, the receptacle 28 being stationary and the receptacle 27revoluble within the stationary circle or graduated scale showingdegrees of circle, so as to be able to determine the axis of acylindricallens when testing for astigmatism. Vi hen it is desired tomove the lens 53 out of the range of vision the handle 50 willbe turnedso as to move the frame 52 down onto the guide bars 55 and 55. When itis desired that the patient shall not see the chart 65 the handle may beturned so as to swing it aside. The frame 57 normally stands against thestop 56 and is held upright by reason of the natural friction of thehollow shaft 60 in its bearings and also partially by beingover-balanced by the weight of the frame 64. When it is desired to movethe lens 62 out of the range of vision the stem 78 should first beturned one quarter turn until stopped by the arm 83, after which thehandle 61 may be turned to move the frame 57 downward In practical use,one or two lenses are placed on the supporter 18, as may be required. Intesting for hypermetropia and presbyopia the concave lens is removedfrom the lens receptacle 27 and the lens 62 is then moved. from the eyeof the patient, chart 65 being withdrawn from view and target 88exposed, and at the distance from the eye at which the chart can best beseen, the number of lens required for the patient is designated and readon the scale 38 as indicated by the pointer 7 9. This measurementrepresents the manifest trouble. To find the latent trouble, chart 65 ismoved into view and the lens 62 is then moved from the eye until thepatient is able to read the chart, or words 65 thereon, with comfort andease, the pointer 7 9 then indicating the number of lens to be used bythe patient for near work. For myopia the proper lens is placed inreceptar-le 28 (receptacle 27 being vacant). This reverses the scale,and lens 62 is moved from the eye until pointer 79 covers 0.000 on scale36 designated for myopes; lens 62 with chart 65 swung aside is thenmoved toward the eyefuntil patient sees target 88 clearly and with ease.The strength of lens is then indicated by the pointer 79 on the scale36. For hyperopic astigmatism target 89 is moved into view before theeye with a clear view through lenses 53 and 62 until some line on thetarget shows plainly; such line will show the axis of astigmatism, and acylinder placed in receptacle 27 of the strength designated on chart andturned to axis indicated by patient will correct error, and the targetwill appear as to any normal eye, all radiating lines being distinctlyseen. The same process is to be followed for myopic astigmatism with theexception that the proper lens is to be inserted in receptacle 28(receptacle 27 being vacant) as for myopia.

Target 90 is used in connection with a double prism revolved byreceptacle 27.

Having thus described the invention what is claimed as new, is

1. An opto refractormeter including a frame base, a housing on the base,a lens-supporter mounted on the housing, a relativelyfixed lens withinthe housing, a target within the housing, a chart supported adjustablywithin the housing, and an adjustable and disappearing lens within thehousing.

2. A11 opto refractormeter including a frame base, an inclosing housingon the base and having a lens-supporter on one end and a door on theopposite end thereof, a relatively-fixed lens within the housing, atarget within the housing, an adjustable and disappearing lens framesupported within the ousing and having a lens thereon, and a chartmounted on the adjustable and disappearing lens-frame to disappeartherewith.

3. An opto refractormeter including a frame base, a housing on the baseand having a lens-supporter on one end and a door on the opposite endthereof, a relatively-fixed lens and an adjustable disappearing lensmounted on the base within tne housing, a chart mounted movably Withinthe housing to disappear simultaneously with the disappearance of theadjustable and disappearing lens, a target mounted within the ho using,and an apertured partition in the housing between the target and thedoor.

4. An opto refractormeter including a base, a housing mounted on thebase and having a lens-supporter on one end and a door on the oppositeend thereof, a plate mounted adjustably on the housing adjacent thelens-supporter and having two apertures therein, a relatively-fixed lensand an adjustable lens mounted on the base within the housing, a chartmounted movably within the housing, a plurality of targets mountedadjustably within the housing, and an apertured partition in the housingbetween the targets and the door.

5. An opto refractormeter including a frame base, an inclosing housingon the base having a lens-su porter on one end thereof, the opposite endof the housing being apertured, a target-frame mounted on the base nearthe apertured end of the housing, a target-holder pivoted to thetarget-frame and having an aperture therein, tar ets mounted on thetarget-holder, a lens-frame hinged on the base and supporting a lens, aguide on the base, a erosshead movable on the guide, a lens-framemounted on the crosshead and supporting a lens, and a chart mountedmovably within the housing.

6. An opto refractormeter including a frame base, a pair of guide-barsmounted fixedly on the base, a lens-frame hinged on the base andsupporting a lens, a crosshead mounted movably on the guide-bars andhaving a shaft mounted rotatively thereon, a lens-frame secured to theshaft and supporting a lens, a chart-frame hinged to the lens-frame thatis secured to said shaft, a chart on the chart-frame, a target-framemounted on the base, a target-holder pivoted to the target-frame,targets mounted on the target-holder, a housing mounted removably on thebase, and a lens-supporter mounted on the housing.

7. An opto refractormeter including a frame base, a lens-frame pivotedon the base and supporting a lens, a plurality of targets mountedadjustably on the base, a housing mounted on the base and having alens-supporter mounted movahly on one end thereof provided with alens-receptacle and also a rotative lens-holder adjacent thelens-reeeptacle, the lens-holder having a lens-receptacle the1;eon, alens-frame pivoted to the base and supporting a lens, a guide mountedfixedly on the base, a crosshead movable on the guide, a shaft journaledon the crosshead, a lens-frame secured to the shaft and supporting alens, and a chart mounted movably on the lens-frame that is secured tosaid shaft.

8. An opto-refractormeter including a stationary frame having a pair ofguide-bars secured thereon, a lens-frame hinged to the stationary frameand having a lens thereon, a crossheadmounted movably on the guide barsand having a lens-frame hinged thereto that has a lens thereon, aplurality of adjustable targets mounted on. the stationary frame, ahousing connected with the stationary frame and having a lens-supporterthereon, and a chart mounted movably within the housing.

9. An opto-refractormeter including a stationary frame, a housingcomprising a frame mounted on the stationary frame and having anapertured partition therein,'one end of the housing having a doorthereon opposite to the partition, a lens-supporter mounted on theopposite end of the housing on the opposite side of the partition, arelativelyfixed lens mounted within the housing, a movable lens mountedwithin the housing, a scale mounted on the housing, a pointer movablewith the movable lens along the scale, a chart mounted movably withinthe housing, a tar et mounted within the housing, and a lamp mountedwithin the housing between. the partition and the door.

10. An opto-refractormeter including a st ationary frame base, aninclosing housing having a slot in its top and mounted on. the base, ascale on the housing top adjacent the slot, a lens-supporter mounted onone end of the housing, a target mounted on the base in the opposite endof the housing, a lens-frame hinged on the base and having a lensthereon, a guide mounted fixedly on the base, a cross head movable onthe guide, a lens-frame hinged on the crosshead and having a lens fixedthereon, and also a shaft mounted rotatively thereon, stops for theshaft, a pointer on the shaft to be moved thereby toward the scale, theshaft being movable into or out of the slot in the housing, and a chartmounted movably in the housing.

11. An opto-refractormeter including a frame base, a housing mounted onthe base, a target mounted on the base within the housing, guide-membersmounted on the outer side of one of the ends of the housing, alens-supporter mounted slidingly on the guide-members, a lens-receptaclemounted on the lens-supporter, a lens-holder mounted rotatively on thelens-supporter, a lens-receptacle mounted on the lens-holder, twolens-frames mounted on hinges in the hous ing and having lenses thereon,one of the lens-frames being adjustable toward or from the other one,and a chart mounted movably within the housing.

12. The combination of a stationary frame, a lens mounted on thestationary frame, a pair of guide-b ars mounted on the stationary frame,a crosshead mounted on the guidebars and having a hollow shaft mountedrotatively thereon, a lens-frame attached to the hollow shaft and havinga hinge-member thereon, a lens mounted on the lens-frame, a charteframehinged to the hinge-memb er and having a shaft attached thereto that isrotative in the hinge-memb er and provided with a pinion, a chartmounted on the chartframe, a spindle rotative in the hollow shaft andhaving a toothed segment thereon that is in engagement with the pinion,and a target mounted on the stationary frame, with a housing inconnection with the stationary frame, and a lens-supporter mounted onthe housing.

13. The combination of a stationary frame, a housing mounted inconnection with the stationary frame and having a door thereon normallycovering an aperture in the housin a targetframe mounted on the station-?37 ary frame opposite to the door, a guide mounted adjacent to thetarget-frame, a target holder pivoted to the target-frame and having aplurality of projections thereon, targets mounted on the target-holder,a pull-rod mounted movably on the guide and having an arm thereon toengage the projections, a relatively fixed lens mounted within thehousing, a movable lens mounted on the stationary frame, and a chartmounted movably within the housing, with a lens-supporter mountedmovahly opposite tothe relatively-fixed lens.

14. The combination of a stationary frame, a pair of guide-bars mountedfixedly onthe stationary frame, a shaft mounted rotatively on thestationary frame, a drive Wheel secured to the shaft, a guide-wheelmounted rotatively on the stationary frame, a crosshead mounted movablyon the guide-bars, a

I drive-belt connected to the crosshead and also with the drive-wheeland the guidewheel, a lens-frame mounted on the crosshead and having achart-frame mounted thereon, a lens on the lens-frame, a chart on J: thechart-frame, and a housing connected With the stationary frame, with arelativelyfixed lens and a target mounted Within the housing, and alens-supporter mounted adjacent to the relatively-fixed lens.

15. In an opto-refractormeter, the comhination of a ltase, an inclosinghousing on the ,adjustalily on the target-frame, a lens mounted in thehousin in proximity to the opposite one of the apertured ends thereof, a

lens-supporter mounted adjacent to said opposite end of the housing, alens mounted adjustahly in the housing, and a chart mounted adjustahlyin the housing.

In testimony whereof, I affix my signature in presence of two witnesses.

FRANK B. HUGHES.

YVitnesses lVlABEL B. HUGHES, WILLIAM D. EoKnNRonE.

